1. Field of the Invention
The present invention relates to a scanner head cartridge that enables a serial printer to function as a reading apparatus by detachably and exchangeably mounting such cartridge on and with recording means of the serial printer.
2. Related Background Art
For a printer having reading means, a structure has hitherto been adopted to exchange recording means held on a carriage with reading means. Generally, such structure is arranged to irradiate the surface of a source document by means of an illuminating device installed on a scanner head serving as reading means, and then, a sensor reads the reflected images of the source document through a lens.
However, the following problems are encountered in arranging the conventional structure that enables a printer to be able to function as a reading apparatus with recording means and reading means, which is exchangeably mountable on it:
(1) When a scanner head cartridge having an optical system incorporated therein is exchanged with recording means and mounted on a carriage, the scanner head cartridge should be positioned in mounting it on the carriage so that the reading surface of a recording medium is positioned optically at a given focal distance of the scanner head cartridge. Therefore, a positioning device to be provided for the scanner head cartridge should be able to define the gap between the scanner head cartridge and the recording medium in a precision higher than that of the gap between recording means and the recording medium. Also, at this juncture, the scanner head cartridge should be mounted on the carriage in such a manner so that the members (a transparent window, lens, and the like, for example), which are included in the optical path to guide the light that carries the read-out information to the interior of the scanner head cartridge, are protected from any possible damage that may be caused by collision with the parts of the carriage. PA1 (2) In the case of an ink jet printer that includes an ink tank in recording means for recording by use of ink, the colors and amounts of ink retained in the ink tank are different depending on the usage of the printer. Therefore, the various modes are adopted for the carriage that mounts recording means on it. Particularly, along the rapid advancement of recording technologies in recent years, new printers and ink head cartridges are produced one after another. As a result, for the respective ink head cartridges whose configurations and mounting modes are different, many kinds of scanner head cartridges should be produced, leading to a problem of extremely high costs of manufacture. PA1 a lower case containing therein optical parts required for reading; PA1 an upper case structured to be coupled with the lower case for covering the open face of the lower case; and PA1 guiding means arranged on the upper surface of the upper case for positioning when being inserted into the carriage.
Further, on the user side, it is necessary for him to purchase scanner head cartridges per printer if he owns several kinds of printers using different ink head cartridges, while he intends to use each of them as the one that can function as reading apparatuses.